MOSCOW: The death toll in Russia’s worst mining disaster in years climbed to 36 on Sunday as officials said 26 workers missing following methane explosions at the pit in the country’s frozen Arctic north could not have survived.

Two blasts ripped through the Severnaya coal mine on Thursday at a depth of 748 meters (2,450 feet), killing four miners and trapping 26 others.

Six more people were killed on Sunday as a fresh explosion hit the mine in the city of Vorkuta in the Komi region, once home to one of the most feared Soviet-era Gulag labor camps.

“According to the expert technical council, 26 (missing) people who were in the mine had no chances of surviving,” Tatyana Bushkova, a spokeswoman for the mine’s operator Vorkutaugol, told AFP on Sunday.

“The rescue operation has been halted,” she added in an e-mailed statement. Anton Kovalishin, a spokesman for the emergencies ministry in the Komi region, told AFP a new explosion in the early hours of Sunday killed five rescue workers and a miner.

“This is a difficult emergency situation, a difficult catastrophe for Russia, for our mining industry,” said Deputy Prime Minister Arkady Dvorkovich, who is heading a special commission established to deal with the tragedy.

He said the families of the victims would each receive one million rubles ($13,000) in compensation. Vorkutaugol is operated by Severstal, the Russian steelmaker controlled by billionaire Alexey Mordashov.

The company was considering whether to flood the mine but now apparently decided to pump it with nitrogen to stop the fire burning at the pit, said Bushkova.

“The chairman of Severstal’s board of directors Alexei Mordashov said that he expects the Severnaya mine to continue its work after the consequences of the disaster have been liquidated,” she said.

“This is the company’s largest mine that produces about a fourth of Vorkutaugol’s output.”

Authorities launched a massive search operation involving hundreds of rescue workers who had been trying to track down the missing despite almost zero visibility, smoke, gas-polluted air and rubble.

Both the company and the authorities had until now refused to declare the missing dead even though rescuers had apparently failed to make contact with them over the past few days.

But the latest explosion forced officials to admit that no one could have survived.

“Unfortunately, we are forced to acknowledge that all the conditions at that section of the mine would not allow a person to survive,” Emergencies Minister Vladimir Puchkov said in comments broadcast by LifeNews television channel.